Richard wrote:Yup, and it gets used regularly. The new bike might allow me to put the 30 back on, but I'm sure if I do, I'll find an even steeper hill.

I would have thought all this fixie riding would be starting to rub off on your geared climbing by now. Not the case?

It's helping. The lower granny gives me an extra ratio over the standard 30 - funny how it doesn't make much difference. Rather than working on the next to smallest cog though, I'm finding I'm still spinning in the lowest cog up hills but getting onto the middle ring earlier and for longer.

It doesn't matter how strong you are, when you're my age, being able to spin is the way to climb hills and the lower the gear the better.

The 26 tooth has been on for well over a thousand kms now. The 105 dr handles it quite well, you just have to be patient with changing from small to middle and if the adjustments aren't right, you'll throw the chain. It's not hurting to carry the thing. (hey Mountgower, the front dr cable will be easier to get to on this bike so I might be able to use your 'pluck the cable' technique to reseat the chain )

Hmm, just remembered, sooner or later, the dog's trailer will be towed up those hills - the 26 stays

I probably should have fitted mtb cranks and bb when the Trek was new, but I didn't and there are times when I run up a decent cadence while pulling the front gear. Nah, the current gearing works - in fact the middle and large ring are just about perfect for me and I certainly wouldn't want to change the middle.

The Trek was built as a workhorse. The Jamis will be a workhorse too, but with sporting pretentions. Maybe the bent will promote her to geared sportster

Kalgrm wrote:You could try the ghetto solution (I would but I'm a cheapskate).

Ghetto solution = a piece of inner tube trimmed to the appropriate width so it can't be seen. No need to flaunt your ghetto in this case .....

Cheers,Graeme

Good idea. I'll look at that. The rubber will be softer on the paintwork than a metal spacer and the 'give' will grip meaning I don't need as much pressure on the clamp. In fact, I'm going to give it a go right now

One ghetto solution successfully trialled. I now have a front dr mounted. It's a bit unsightly, but I'm not sure how I can going to trim the rubber while it's mounted on the bike and trimming it first then trying to get it to fit proved too much of a trial for my patience (I need two layers of rubber). Still, solutions will be found

Thanks for that Graeme (mind you, I haven't hooked up the cable so I can find out if it stays put under pressure )

For trimming the excess rubber, could you slide those rubber shims and the DR onto any old piece of frame or similar diameter pipe, and trim it there? That would give you the right support to be able to trim it neatly with a good sharp blade.

That way you don't need to worry about the paint work on the Jamis, but you end up with a very neat trim job.

The problem I've got is that I need two layers of bike tube and they slide over each other as you're putting the lot together. A piece of car tube would be perfect ... but when was the last time you saw a car tube?

I'll look around for a few alternatives (I'm sure there's a purpose built shim I can buy) and if I find I'm using the bike tube, I might use a bit of rubber glue to hold the layers together.

There'll be a neat solution to this. The main thing is that I've been able to get her going

The thing about rubber is that it will compress as you tighten the clamp. That means you need a thick piece of rubber to provide the desired effect.

The non-ghetto shims are made of plastic, which is why I suggested the ice-cream container after sleeping on the problem over night. I've got a couple of them in my box of tricks out the back, but getting them to you would take longer than just nicking around to the LBS (they will have heaps of them left over from builds).

PS - cut a patch into pieces to be attached to the shim. That will provide 2" of patch.

Cheers,
Graeme

Think outside the double triangle.---------------------Music was better when ugly people were allowed to make it ....

My triple chainring set is 26, 42, 52 - yup, that's some jump from the granny to the middle.

Regardless of what the rear derailer is, the type of front derailer is mostly determined by the size of the large chain ring - 52t ring will mean a road series derailer is required. Next is the top or bottom pull for the cable.

My triple chainring set is 26, 42, 52 - yup, that's some jump from the granny to the middle. Richardstalled again

I'm wondering if there is any benefit to be gained in switching the front rings to something like 28 & 40. Leave the 52 as it seems to work OK.
This will reduce the gap from little to mid by 4 teeth. & make the shift a little easier. This amounts to a 25% reduction in the size of the jump from little to middle but only a 20% increase [2 teeth] from middle to big.
I remember that I bought a new Stronglight crankset for my mountain tour in '86 with 28,38,48 rings. It was a little slow in the highest ratio, but then again, so am I so it was all good.
To help things along I had a three column ratio chart secured to the stem so that I didn't screw up the changes & get a bad combination.

I used only a 5 speed cluster, didn't need anything more, & I'm trying to remember what the largest sprocket was. I'm fairly sure it was a 34 tooth one [my mate had a 38] & this gave me a 24" low gear which was used only once & even then only for about 25 yards. This was on a bike that weighed 81 lbs [36,74Kg] loaded & ready to ride.
I remember reading somewhere that anything much below about 20" of gearing is so low, & slow, that riders have difficulty keeping the bike upright.
I had 27" wheels, so 700C or 26" wheels should theoretically gear you lower than that. How low do you want your granny gear anyway?

europa wrote:Just rang the lbs. Yes, proper shims are available ... but they're out of stock

Ah well.

Richard

You could use the coke can or thicker aluminium can type shim as temporary use. standard can diameter will give fraction more than 2 layers of wrap.
At a measured thickness of approx 0.1 mm, would need 8 strips. Make the bottom most layer a little wider and roll the edge up and over the top to contain the layers (laminations) together. Just enough to hold the layers, and so that it can be de-laminated when the shim arrives.

Kid_Carbine wrote:I'm wondering if there is any benefit to be gained in switching the front rings to something like 28 & 40. Leave the 52 as it seems to work OK.

Nope, no way I want to touch that middle ring. It provides an almost perfect range for my riding - a lazy rider could ride the middle all day. As far as hills go, when I can't pull the big cog on that middle ring, I'm in genuine granny country. In addition, it combines perfectly with the 52 big ring. There is one step in the gears when you change between the large and middle rings, you never have to do a double shift yet there's a serious difference between the two.

Consequently, I'd only change the middle with a corresponding change to the big ... and that would result in my changing rings more often as I get onto the smaller cogs at the back - although I can use the entire cassette on the middle ring (with no rubbing on the dr and no trimming needed or available on that dr), I am very aware of cross chaining.

Basically, rolling or climbing country is middle ring, flat is large - it's a mix that works well for me ... and you watch that experience be rendedered useless by the new bike

But yeah, I've considered gears before. The best solution is the small granny - it gets me up the hills I have to climb, allows me to ride the rest efficiently for the price of slow shifts off the granny and the occasional double change onto and off the granny. I can live with that for the few times I need the granny, but that double change would drive me mad if it was introduced on the middle to big ring - this is why I can't understand the mania for 'compact cranks'.

The tiny granny is extreme, but the whole setup works well if you consider the granny a gear just used to get up very steep hills. Even if the lighter bike and growing leg strength allow me to fit a larger granny, I'll probably keep it for towing the trailer up hills, something I've avoided so far.

I dropped into my lbs today, showed the mechanic the dr and explained the problem. He turned to his workbench, opened a drawer and took out a strip of rubber - didn't even hesitate. Mind you, this is quite thick and very tough - think car tyre or the stuff they give you to put under light fittings.

Front derailleur mounted. You can see the rubber spacer. Basically, I pushed the rubber into the mount, used a biro to trace the mount, then cut to the line with a pair of strong scissors (easy job). The rubber is way too thick, which is good. This meant a lot of trimming at the 'join' end, gradually getting it shorter and tapering the end of the rubber until I could get the clamp to close enough to fit the bolt (using a pair of multi-grips squeezing the heck out of the dr clamp in the process). The tricky part was getting the dr in the righ place - though it doesn't look it here, it just clears the large ring and is parallel with the rings once the clamp was done up tight. Tightening the screw forced the rubber out a bit which is why it is is sitting a bit proud now. About an hour of stuffing about to get it right

I think this'll work - it feels solid enough. If it's not perfect, I'll invest in the right sized dr rather than pfaffing about with more shims.

Richard

Last edited by europa on Tue Nov 20, 2007 2:52 pm, edited 1 time in total.

Front brake mounted. This has actually been on for a day or two now. No problems with mounting the brake itself but you'll note that the cable is a wee bit too short causing too tight a curve in the cable where it comes out from under the bar tape. There wasn't much difference in cable outer length between that curve being too tight and having an S bend in the cable. I had it spot on, fitted the cable itself, pulled everything tight and had the outer move slightly somewhere which resulted in the tight curve you see. I don't think it'll matter much but if it does, it's just a matter of moving the light mount you can see on the bars - it traps the outer cable and moving it will allow more curve in the cable.

Rear brake mounting.
Another story. This brake came with the long nut used for the front brake. I priced a new one from the lbs but they only had them as a full mounting bolt assemble for about $40 Stuff that for a joke. It's just a long hollow nut right? So I cut it to length ... and then discovered that it's not threaded all the way through I was able to order the right nut from ChainReaction with some other stuff and in the meantime, am using the big nut you see here as a spacer.

For those who've never bought brake cable before, this is how you get the generic cables (those who pay for 'ultegra' cabling may find their experience different).

The trick is that there are two fittings on the cable, one at each end (surprise, surprise). If you look closely, you may be able to see that they are different. One end is the round end used in STi systems, the other is the 'T-shaped' end used on older brakes and mtb systems. The trick is to cut off the right end ... yes Virginia, I have come close to chopping off the wrong end but have managed to avoid that mistake

Here are the rear brakes again, this time with cable attached.

Technically, you could say that this outer is too short too, but if I made it longer to get a straight run out of the upper stop, I'd introduce a slight S bend into the outer. This is a product of the size of the frame. Smaller frames have a smaller drop between that last stop and the brakes and can get a more perfect cable line.

You'll also notice the sleeve on the end of the cable. These are crimped on to stop the cable fraying and it's well worth buying a packed and using them - they aren't essential but I've stuffed around with too many frayed cables to begrudge the small cost.

You cut off the (looking at the picture) left side, but where did you cut it.

Also then when you had to thread it from the rear brake to the bars, which way did you go? Did you have to take anything off the bike first? Like when you put a hose in the nosel was anything threaded on before it was tightened?

Mitch.

Clarity is the cure to stupidity.

SOME PEOPLE ARE LIKE SLINKYS. NOT REALLY GOOD FOR ANYTHING BUT THEY BRING A SMILE TO YOUR FACE WHEN PUSHED DOWN THE STAIRS.

You cut off the (looking at the picture) left side, but where did you cut it.

Also then when you had to thread it from the rear brake to the bars, which way did you go? Did you have to take anything off the bike first? Like when you put a hose in the nosel was anything threaded on before it was tightened?

Mitch.

Clarity is the cure to stupidity.

Nah, there is a lot that is screamingly obvious ... once you've done it, and this isn't intended to be a blow by blow manual.

You cut the end off as close to the fitting as practical, then shorten it to the correct length later on.

When fitting brake (and gear cables for that matter), you pull the inner out of the outer. You then cut the outer to length (trial and fit on the bike), clean up the ends and put on the end caps.

As to how you fit the inner cables to the bike, there are two methods, depending on the system you're using and many variations within that depending on how the cables are routed on the bike.

The older road systems and the mtb systems I've played with, have you insert the inner back into the outer, and then fit the whole cable to the bike. You can do this because the seat that holds the end of the cable has a slot cut in it. You feed the cable through that slot then pull it to seat the end fitting home. I'm not going to go into any more detail here. Sorry.

The STi system is such that you have feed the cut end of the inner through its seat (it doesn't have that slot in the side) and pull it right through until the fitting seats home in its seat. You then feed the outer over the inner and install it to the bike. Again, to go into detail requires a lot more talk than is appropriate here. Maybe another time.

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